High Definition Media Interface (HDMI) is transmission interface defined by the HDMI Licensing, LLC Organization. HDMI is a common audiovisual standard for the transmission of high definition video, audio, and related media signals. In this context, HDMI defines an interface for transferring uncompressed video and compressed or uncompressed audio data from a source device to a sink device. HDMI has generally been relied upon as a digital replacement for conventional analog video standards.
The HDMI can simultaneously transmit uncompressed digital video and audio data streams. Currently, HDMI may be the most widely used audio and video transmission interface in consumer electronics. HDMI is compatible with the HDCP (High-bandwidth Digital Content Protection) digital rights management technology, and provides an interface between any compatible digital source device, such as a set-top box, a Blu-ray® digital-versatile disc (DVD) player, an HD DVD player, a personal computer, or a video game console, for example, and a compatible sink device, such as a digital television, computer monitor, display, etc.
In the standard HDMI, a signal line for Transition Minimized Differential Signaling (TMDS) can be used for transmitting audio data, video data, and associated control information; a signal line for Display Data Channel (DDC) can be used for transmitting the Extended Display Identification Data (EDID) and the information associated with the HDCP key; a signal line for Consumer Electronic Control (CEC) can be used for transmitting the operation control data between equipment; a signal line for Hot Plug Detect (HPD) can be used for transmitting information associated with the connectivity state of the equipment; and a 5 voltage power signal line and a common ground signal line can be used for providing an auxiliary power supply to the receiving device and providing a unified reference ground level for all single-ended signals.